肺癌影像引导放疗人工图像配准方法分析  

Reproducibility Evaluation of the Manual Alignment Method for Kilovoltage Cone-beam CT Guided Radiotherapy

作　　者：王艳阳[1] 傅小龙[1] 夏冰[1] 吴正琴[1] 樊旼[1] 杨焕军[1] 徐志勇[1] 蒋国樑[1] 

机构地区：[1]复旦大学附属肿瘤医院放疗科复旦大学上海医学院肿瘤学系,上海200032

出　　处：《生物医学工程学进展》2008年第3期156-160,共5页Progress in Biomedical Engineering

基　　金：卫生部临床学科重点项目(2004468);上海市科委重点项目(34119814)

摘　　要：目的分析千伏锥形柬CT(KVCBCT)引导肺癌放疗人工图像配准法的重复性。方法选择16例在我院行根治性放疗的非小细胞肺癌患者,每周行KVCBCT在线引导体位校正一次,获取患者KVCBCT影像。图像配准选择肺尖和椎体作为参考标记,在矢状位、冠状位和横断位等中心层面上配准患者KVCBCT影像和计划设计CT影像。比较同一名医生相隔一周两次配准,不同医生之间配准和医生与技术员之间配准结果的差异,用于评价KVCBCT引导肺癌放疗人工图像配准法的重复性。结果同一位医生相隔一周两次配准同一幅KVCBCT影像与计划设计CT影像,配准结果在患者左右(LR)、头脚(SI)和前后(AP)三个方向上,差值大于3mm所占的比例分别为:0,13%和6%。不同医生之间的配准结果在LB、SI和AP三个方向上,差值大于3mm所占的比例分别为:11%,19%和14%。医生与技术员的配准结果在LR、SI和AP三个方向上差值大于3mm所占的比例,分别为:16%,27%和27%。结论KVCBCT引导肺癌放疗人工图像配准法的重复性有待进一步提高,尤其表现为不同医生,医生与技术员之间应用该方法的重复性较差。KVCBCT引导肺癌放疗的图像配准方法需要进一步研究。Objective To evaluate reproducibility of the manual alignment method for kilovoltage cone - beam CT guided lung cancer radiotherapy. Methods sixteen non - small cell lung cancer patients entered this study. Weekly on - line KVCBCT guided set - up error correction was performed. A total of ninety - six pretreat- ment KVCBCT images were available for analysis. The landmarks of the manual alignment included the lung top and spine around the isoeenter Images were aligned in three dimensions, and the LR （left- right） , SI （superior -inferior）, and AP （anterior- posterior） components of translation of the target isocenter were documented and analyzed for each registration. Intra - observer variability was investigated： at least one week after treatment all KVCBCT studies were reexamined by the same physician. Additionally, all KVCBCT studies were examined by a second physician, a radiation therapist and inter- observer variability was tested. Results The intra- observer variability of the manual registration method was investigated. All CBCT studies were reevaluated by the same phy- sician. Compared with the original results, the percentage of the more than 3 mm differences in LR, SI, and AP directions are 0,13% and 6% , respectively. The percentage of the more than 3 mm differences in LR, SI, and AP directions between two physicians are 11% , 19% and 14%. The difference of the registration results between radia- tion therapist and physician in LR, SI, and AP directions are 16% ,27% and 27%. Conclusions The reproducibility of the manual alignment method was poor, especially in the inter - observer evaluation. The optimal a- lignment method for KVCBCT guided lung cancer radiation needs further research.

关 键 词：影像引导放疗 千伏锥形束CT 图像配准 肺肿瘤 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]